Interactive input systems that allow users to input ink into an application program using an active pointer (eg. a pointer that emits light, sound or other signal), a passive pointer (eg. a finger, cylinder or other suitable object) or other suitable input device such as for example, a mouse or trackball, are known. These interactive input systems include but are not limited to: touch systems comprising touch panels employing analog resistive or machine vision technology to register pointer input such as those disclosed in U.S. Pat. Nos. 5,448,263; 6,141,000; 6,337,681; 6,747,636; 6,803,906; 7,232,986; 7,236,162; and 7,274,356 assigned to SMART Technologies ULC of Calgary, Alberta, Canada, assignee of the subject application, the contents of which are incorporated by reference; touch systems comprising touch panels employing electromagnetic, capacitive, acoustic or other technologies to register pointer input; tablet personal computers (PCs); laptop PCs; personal digital assistants (PDAs); and other similar devices. Although these interactive input systems are able to recognize handwriting well, their ability to recognize and represent the meaning of hand-drawn objects and in particular, charts or tables, has been limited.
Microsoft Office software includes a feature that enables tables to be created by moving a cursor over an open document. During table creation, cursor movements over the open document are translated immediately into one of rectangles, squares and straight lines. Although tables can be created, the functionality of this feature limits its ease of use in interactive input systems that accept freeform or handwritten ink as input. As will be appreciated, improvements in hand-drawn table recognition are desired.
It is therefore an object of the present invention to provide a novel method and tool for recognizing a hand-drawn table.